So far, my posts in the ‘Successful Search Engine Marketing’ series have focused on techniques which will come in useful when buying traffic on any search engine. However, all the keyword, ad text and landing page optimization in the world will only get you so far if you’re buying traffic from the wrong places. In this fourth post, I’ll be addressing this issue by giving you some tips on which traffic sources offer good value for money, and which ones are best approached with caution.
Which search engines should I buy my traffic from?

When they think about search, the company which immediately springs to mind for most people is, of course, Google. The statistics bear this out pretty clearly: according to Nielsen NetRatings, in November 2009 Google served 15.4 billion page views in the US alone. By comparison, Yahoo Search served 2.7 billion impressions and Microsoft’s ‘Bing’ engine served almost 2 billion. No other search engine passed the 1 billion mark. In many European countries, Google’s share of searches is even greater than in the US, topping 90% in markets such as Germany. As a result of this, advertisers also almost invariably start with Google when thinking about SEM, and many never investigate the other options in the market.

While this is understandable, in my view it’s a mistake to restrict yourself to Google AdWords, for reasons I’ll come to later. Nonetheless, it is the obvious place to start, since it is difficult to imagine a successful SEM strategy which doesn’t include Google. Not only does Google dominate its rivals when it comes to traffic volumes, it also tends to set the standards which other search engines follow in areas such as advertiser policies, how to determine ad quality, and targeting options available to advertisers – so familiarity with Google will stand you in good stead when advertising on other engines. For people new to SEM, Google also offers clear, detailed help content. Google’s superior search volumes, combined with delivering traffic of a consistently high quality to advertisers, means that most advertisers should expect to spend the majority of their SEM budgets with Google, though the extent to which this is the case will differ according to the relative market share each engine enjoys in the countries in which you are advertising.

Despite Google’s many advantages over competing search engines, I would still encourage anyone who is serious about driving traffic to their sites via SEM to experiment with Google’s largest rivals. The offerings from Yahoo! and Microsoft, Yahoo! Search Marketing (commonly known as YSM) and Microsoft AdCenter, both operate in much the same way as Google AdWords: keywords are organized into Campaigns and AdGroups; different ad text variations can be rotated for each Ad Group; and a ‘Quality Score’ measure is used to denote the relevance of your ads for each keyword. These shared attributes across engines makes it relatively simple to take your existing Google AdWords campaigns and apply them to YSM and AdCenter – indeed, Yahoo and Microsoft have both made conscious efforts over the last few years to align their systems more closely with AdWords partly in order to make it easier to transfer campaigns from Google.

Nonetheless, ease of use alone is not enough of a reason for advertisers to invest their time and money on YSM and AdCenter. Thankfully, both offer a few other compelling reasons to advertise with them. Firstly, the volume of traffic both offer is worth exploiting, even if it is lower than Google. In the US for example, replicating your Google campaigns on YSM and AdCenter should increase your SEM traffic by approximately 25-30% compared to advertising on Google alone. Secondly, lower competition for keywords means that in our experience CPCs have tended to be around 25-50% lower on YSM and AdCenter than on Google. Thirdly, YSM in particular rivals Google in terms of traffic quality – we’ve even noticed the Revenue per Click being higher from YSM than Google on some segments of keywords.

Beyond Google, YSM and AdCenter, there are other search networks out there which could increase your website’s reach even further, such as Kanoodle and FinditQuick. However, I would recommend exercising caution when deciding whether to invest the time and resource in working with these ‘Tier 2’ search networks. Firstly, there is a significant gap between the traffic volumes you can expect from such networks compared to the ‘big 3’ of search. Secondly, most Tier 2 networks operate differently to AdWords – for example, rather than having the concept of AdGroups, many networks require unique ad text to be generated for each individual keyword. While this is not necessarily a bad thing, it does limit your ability to simply download your Google campaigns and replicate them. Finally, the traffic quality from many Tier 2 networks tends to be significantly lower than for traffic sourced from Google, YSM and AdCenter. Though CPCs on these networks tend to be low, I’d recommend thoroughly exploring the different options to increase your website’s traffic offered by Google, YSM and AdCenter before considering buying traffic from Tier 2 networks.

Targeting your traffic

Once you have decided which search engines you want your ads to appear on, you can still make a massive difference to the reach and effectiveness of your campaigns by ensuring that you are targeting your ads to the most relevant subset of their audiences. The range of different targeting options available from Google, YSM and AdCenter is too large to do them all justice in one blog post, so I will be restricting myself to three of the most important here: Languages and Locations; Search Networks; and Content Networks. Some of the other targeting options available, such as Match Types, have been covered in previous blog posts in this series, while I will be discussing other possibilities such as Time of Day bidding in future posts.

Languages and Locations

Given the global reach of the largest search engines, ensuring that you are only paying for your ads to be shown to speakers of certain languages or users in certain countries is an absolute necessity. While targeting by language and location may seem an obvious aspect of search engine marketing, many advertisers neglect to focus on these basic settings for their campaigns and waste considerable amounts of money as a result.

When it comes to languages, search engines match the languages you are targeting with the language preferences their users set for their search interface. For example, if you decide to target your ads solely to English-speaking users, only those search engine users who have their language preferences set to English will see ads for your website. There are a few best practices that I would recommend following when it comes to language targeting. Firstly, you should only target your ads to languages in which your website operates. If you don’t have a website in Spanish, targeting ads to Spanish speakers may increase your reach but is unlikely to lead to a significant increase in conversions. Secondly, if you do have a website in a number of different languages, make sure you set up separate campaigns to target each language, and ensure your ads in each campaign are in the relevant language. To continue the example above, even if you do have a Spanish-language website, if you’re targeting Spanish-speaking search engine users with English ads, you’re unlikely to have much success. Finally, if you operate websites in multiple languages, when integrating merchants into your websites, you should make sure that the language of website and integration is matched.

Search engines also give you multiple options to target users in specific locations. Though the exact parameters vary by engine, in most cases you can target by continent, country, region or city. Each engine also uses slightly different logic to determine whether a user is fits within each of these different geographical groupings. However, in broad terms engines tend to consider three aspects: the domain extension on which a user is searching (e.g. users of Google.de are considered to be located in Germany); whether the search term used specifies a geographic location (for example a user searching for ‘San Francisco car dealers’ will be deemed to be eligible to see ads targeted to San Francisco); and the physical location of the searcher as determined by their IP address. This last technique can be used to determine whether a user is eligible for ads targeted to certain regions or cities, as well as being used to identify which country a user is searching from in the event that the domain extension does not already reveal this – for example, users searching on Google.com with a UK IP address will get ads targeted to the UK rather than the US. You can find more information on exactly how Google’s geo-targeting system works here.

I have to admit that I have relatively little experience with geo-targeting by city or region, so I will leave advice on how to get the best out of this option to users with more expertise in this area – indeed, if there are any readers of this blog post who have extensively used this functionality, please feel free to comment on how best to make this work! However, I would recommend that every advertiser should use location targeting for their ads to limit visibility by country at the very least. If your site has a significant amount of content which is specific to one country (for example displaying products which all have prices listed in US dollars), my advice would be to target ads for that website to only show to users in the same country. For those of you utilizing eBay Partner Network’s geo targeting functionality, if eBay is the major portion of your revenue I would recommend basing your decision about which countries to show your ads to on which eBay programs you are signed up to. For example, if you are only signed up to the eBay US and CA programs, I’d target your ads only to users in the US and Canada. When targeting your ads to multiple countries, I would advocate using different campaigns for each country you are targeting for two reasons. Firstly, this will make it easier to ensure your ads are in the correct language for each country; and secondly, traffic from different countries is likely to convert at different rates and therefore you are likely to see a variance in revenue per click for traffic from each country. Having keywords separated into different campaigns by country will therefore allow you to vary your bid for the same keyword in each market to reflect these differences.

Search Networks

Google and YSM both offer advertisers the choice of having your ads appear only on their properties (i.e. Google and Yahoo Search), or across the whole of their ‘Search networks’. Choosing the latter option will see your ads appear against relevant searches performed on sites such as eBay, Amazon and Shopping.com.

In order to make the best possible use of these Search networks, it is a good idea to implement referring URL tracking so that you can see the performance of your ads on each of the sites within these networks. Google and YSM both provide reports on the number of clicks coming from each of these domains, and all good analytics solutions should allow you to track conversions by referring domain as well.

In my experience, traffic coming from the Search networks tends to convert at a level 10-20% lower than traffic coming directly from the Google and Yahoo Search properties. However, this average can vary significantly between sites – some sites within the network perform better than Google and Yahoo themselves, some perform significantly worse.

While the Google and YSM Search networks operate in a very similar manner, the tools they give you to optimize your ads’ appearance on their networks have some key differences, with YSM offering more flexibility to advertisers. YSM allows you to block your ads from appearing on up to 250 domains, sub-domains and sub-directories across their Search network. This can be very powerful for cutting out spend on poor-performing parts of the YSM network. Google, however, does not offer the same functionality – your only option here is whether or not to have their Search network enabled for your ads, though advertisers have been pushing Google to rectify this for some time. To get round this, we ask Google to block the domains of some of our very large publishers from appearing on eBay, although of course that doesn’t prevent their ads appearing anywhere else on Google’s Search network and we will let the affiliate know. This ensures their site’s ads do not appear on eBay and inadvertently lead to roundtripping.

While it is not possible to stop your ads from appearing on individual sites within Google’s Search network, there is a technique you can employ to make your bids on the Search network more reflective of the quality of that traffic, though I should mention that this is not officially endorsed by Google. The methodology is as follows. Firstly, run your campaigns across Google and the Search network, with referring URL tracking in place. Secondly, analyze the difference in performance between Google and the other parts of their Search network. When doing this, you should ensure that you have been running the campaigns for long enough to have a reasonably consistent trend in the relative performance between traffic from these two groups. Thirdly, if there is a noticeable difference in performance between Google and its Search network, create duplicate copies of your existing campaigns. Switch your existing campaigns to appear only on Google, and set your new, duplicate accounts to appear only on Google plus the Search network (you cannot choose to exclude Google). Finally, set the bids for keywords these two sets of campaigns to reflect the difference in performance of Google and the Search network. For example, if your revenue per click from the Search network is 15% lower than from Google, set your Max CPCs for the Search network 15% lower than you would do for the same keywords in your Google-only campaigns.

Assuming all other components of your Quality Score are equal between your Google-only and Search network campaigns, your higher bids on Google-only will force your ads for these campaigns to appear in preference to your Google plus Search network campaigns. Your Google-plus-Search network campaigns will therefore have the vast majority of their traffic coming from the Search network, with your differentiated bids roughly equalizing the ROI between the two sets of campaigns. Not only will this save you money on Google’s Search network, you will also be able to bid higher on Google itself (and therefore drive more high quality traffic from this source) than would be the case if your campaigns contained a mixture of Google plus Search network traffic.

I should mention a few caveats to the above approach. This is something of a ‘hack’, rather than a Google-approved method, so don’t expect to receive too much support from your Google account manager in implementing it. It’s also not 100% effective in separating out Google versus Search network traffic, for a couple of reasons: firstly, since in some cases keywords in your Search network campaigns may have a higher Quality Score than in your Google-only campaigns, cancelling out the CPC differential and causing keywords from your Search network campaigns to show on Google; and secondly, as part of Google’s ‘sandbox’ for calculating Quality Score, keywords from your Search network campaigns may occasionally be run on Google even if the Google-only variant of the same keyword has a higher Quality Score and Max CPC. Nonetheless, I have found this method to be largely effective in improving ROI from my Google campaigns overall without sacrificing traffic volumes.

Content Networks

Google, YSM and AdCenter also offer advertisers the ability to have their ads displayed on non-search sites via their Content networks. All three use contextual targeting to match an advertiser’s keyword-based ads with the content of relevant web pages. On average, traffic from these Content networks tends to perform worse in terms of Click Through Rates and Revenue per Click than traffic from the Search networks. As a result, these networks do not always have the best reputation with advertisers. However, if used carefully, advertisers can generate additional traffic at good ROIs from these networks, and should not automatically rule out using them altogether. I should mention, though, that in my experience the YSM and AdCenter Content networks have driven too little traffic and too low a quality of traffic to make them worth investing a great deal of time on; my advice would be to stick with Google’s Content network unless you are really desperate for extra traffic.

The first rule to follow when buying traffic from these Content networks is to ensure that the amount you are paying for the traffic is in proportion with the value of that traffic – in most cases, this will mean setting a lower Max CPC for your keywords on Content than on Search. The way in which you organize your keywords into AdGroups is even more important on the Content networks than for Search. The more you can form your AdGroups around a small number of keywords tightly correlated to an individual subject, the better the chances of your ad being successfully matched to relevant pages within the Content networks. You can also choose to block your ads from appearing on groups of sites (e.g. adult) or individual domains, sub-domains and sub-directories within the Content networks (including Google, which as mentioned above does not enable advertisers to do the same on its Search network). Diligent use of this domain blocking functionality can significantly increase your ROI while allowing you to benefit from the extended reach offered by Content networks.

In the next post in this series I’ll be delving into the question of how you should determine what to pay for your Search Engine traffic, and how you should best optimize this spend in order to get the best possible return on investment from your SEM activities.

Chris Howard

European eBay Partner Network team leader and one time eBay UK SEM manager